Piston ring



Oct. 20, 1931. sc m 1,828,001

PISTON RING Filed Feb. 24. 1931 Mm ml L ew: "1 w" 3 a INVENJOR G/PGE SCHNEIDER B i W A T T OFNL'Y atented ch 2% 333% new GEORGE SGHNEIDERQOF SAGINAW, MICHIGAN, ASSIGNOR TO WILGOX-RICH CORPORA- TION, OF DETROIT, MICHIGAN, A CORPORATION OF MICHIGAN rrs'ron' RING Application filed February 24, 1931. Serial No. 517,785.

has an aperture through its bottom to permit oil to pass from the pocket through the inner 19 back wall of the ring.

Usually these apertures have been sawkerfed but sometimes one or more holes have been bored through the bottom of the oil pocket in lieu of the saw-kerfed slots. In :5 either case the effect has been to divide the periphery of the ring into alternating zones of varying degrees of stiffness, i. e. resistance to bending. Those zones wherein the oil aperture penetrates the bottom of the oil pocket constitute the weakest parts of the ring and the stiffest parts are at and ad]acent to the solid parts or dams that separate each 011 pocket from its neighbors.

Obviously, the tendency of such known rings, when sprung into place on a piston. is to flex unevenly an exert non-uniform intensity of pressure outwardly against the .cylinder wall.

Moreover, in the known ring structure to which reference has been made the oil pockets have been completely isolated from communication with each other by the intervening dams. Sometimes graphitic carbon has sealed the oil slot or aperture associated with a pocket, causing the ring area corresponding to that pocket to function improperly as to its lubrication.

It is an object of my invention to secure the 1.:- advantage of more nearly uniform flexing and thereby to attain more nearly uniform pressure of the ring against the cylinder wall without sacrificin either the known advantages of (a) perip eral oil pockets or (b) of oil slots or apertures that connect the pockets I with the space inside .the ring.

A still further object of my invention is to overcome themenace to perfect oil-sealing of the cylinder wall areas by providing means for maintaining a small but sufficient degr'ee of oil communication between the several hitherto non-communicating pockets.

The means by which the stated objects of the invention are attained consists in a novel arrangement of old elements, namely, the resilient ring, the peripheral oil pockets and the oil slots. By such rearrangement, described and claimed herein, the stiifness of the least resilient parts in the prior ring structure has been reduced and the parts that W were weakest have been stiffened. The successive oil pockets have also been put into communication with each other.

With the above and certain other objects in view, which will appear later in the specification, the invention comprises the devices described' and claimed and the equivalents thereof.

In the drawings Fig. 1 is a plan view of a ring embodying my improvement, the ring being shown partly in section and in its compressed or gap-closed position.

Fig. 1a is a fragmentary plan view, in section, showing two known types of rings to whipih my improvement is adapted to be applie I Fig. 2 is a view of the cylinder-contacting face of the ring of Fig. 1, developed.

Fig. 3 is a plan view of a ring, partly in section, showing a modified embodiment of my invention. I

4 is a fragmentary view of the working ace of the ring shown in Fig. 3, developed.

Fig. 5 is a greatly enlarged view in rsp'ective of a part of a ring made accor ing to Figs. 1 and 2.

As is clearly shown in Figs. 1, 2, 5, the ring is made of a bar of metal .1 rectangular in cross section, of appropriately circular shape and provided with the usual gap-cut 2.

A plurality of oil pockets 3 extend around the outer periphery of the ring, being separated from each other by damportions 4, in known manner. I

In a ring embodying my invention in the preferred form now under discussion the oil slots are cut through the dams 4 from the Q l er periphery of the ring to its inner pe- I riphery and parallel, or approximately partoms 6 of pockets 3 instead of through the middle part only of bottoms 6, as has been done heretofore, not only is the stiffness of the ring at the dam 4 reduced, but also the zones defined by the pockets 3 are increased in stiffness by reason of the fact that the oil slots, being in lengthwise staggered relation to the pockets, provide at the bottom 6 of each pocket and midway its length a body 6a of reinforcing metal which heretofore wasabsent.

Moreover, each oil-slot 5 provides a relatively restricted but sufficient channel for oil communication between adjacent pockets, 1 and the arrangement of the slots and pockets is such that there can always be oil communication betwen adjacent pockets 3, 3, even though one of the slots 5 becomes blocked where it passes through the inner face'of the ring. The communication referred to is maintained peripherally around the ring by reason of the fact that the pockets 3, 3 are connected to each other by the slots 5.

Changing the former locations of the elongated saw-kerfs 5 to the herein described new locations, in which they are made to bisect the dams 4 between pockets, constitutes what I consider a primary part of my present invention, since it results in attaining all of the operating advantages above enumerated.

In vcertain cases intercommunication between the oil pockets at their bottoms 6 is not so important and it is not desirable to cut saw kerfs in the rin In such cases I have employed a modi ied ring structure which is illustrated in Figs. 3 and 4. Here a number of shallow individual oil pockets 3, 3a are formed around the outer periphery of the ring and are separated by dams 4a through which radially directed holes 5a are bored to connect the outer face of the ring with the space behind the ring. Thus outside the bored dam 4a is formed a shallow peripheral channel 7 that provides the restricted but adequate amount of oil .communication between each oil hole 5a and the adj acent pockets 3, 3a. The oil hole 5a weakens the structure of dam to and increases the resilience of the zone in whichthat dam is located, and to that extent serves the same purpose as does the dam-severing saw kerf structure of Figs. 1, 2, 3.

By the means above described the resilience of the ring has been rendered more uniform all around its periphery and the ring has been made to exert a more uniform cutward pressure against the cylinder wall, assuring better oil film distribution and producing a more perfect oil sealing film on the cylinder wall than has heretofore been ob tainable.

Having thus described my invention, what I claim and desire to secure by Letters Patother and separated by dam portions integral with the ring, and apertures extending entirely through the ring at said dam portions, and establishing communication between the inner face and the outer face of the ring.

In testimony whereof, I affix my signature.

GEORGE SCHNEIDER. 

